static electricity and varnishing

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AkDan
Posts: 172
Joined: Wed Oct 27, 2004 2:19 pm

static electricity and varnishing

Post by AkDan »

Well it's time to varnish. Have spent the past couple of days cleaning up. Hopefully tomorrow nite I'll hang the "spray booth" again in preperation to varnishing.

Tonight I did some cleaing up of the dust on the boat. Did the outside and then rolled it over for the inside. Was just about done when I heard a cracking sound. Mind you I'm balder then a baby's butt and could steel feel what little fuzz I have stand to attention.

All the dust that I kicked up cleaning the shop promptly stuck to the boat. So how does one go about eliminating it?

It's coooold outside right now, lows pushing -50F Not sure what the dewpoint is, or really how it affects this.

any other varnishign tips? Foam or bristles? Roll on and tip off? Spray on (was thinking of the preval co2 sprayers). Any other goodies and must knows and not to do''s?
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Glen Smith
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Location: Baie-St-Paul, Quebec, Canada

Post by Glen Smith »

I haven't discussed this topic in a very long time. In the old days, way back when................................................boat-builders used to place a chain over the boat hull and ground the chain to discharge the static electricity. A few years ago a builder I know was having this problem and it was even preventing the varnish from setting. I suggested that he place a bare copper between the boat and a cold water pipe and leave it overnight. The next morning, the varnish was dry.

Try to avoid building up static in the first place by not running your hand over the wood too often. Vacuum off any dust then place a copper wire over the hull and ground it. Leave for a few hours or overnight. If the static has discharged, remove the wire, do a final light wiping with a tack cloth and go to work.

For applying varnish I like to use a 3" foam brush. Filter a quantity of varnish through a paint filter into another clean container. Add thinner if necessary for good application and use Ted's brushing technique explained in his books.

Oh yes, I forgot to mention something important. Do what you can to raise the humidity in the work area. Install a humidifier, or if the floor is concrete, wash it several times with a mop and leave it wet. This will raise the humidity, lowering the static and also the dust. Most spar varnishes prefer a humidity level around 50% for easy application and proper drying time. Don't forget, the first coat of varnish can take up to 3 days to harden in some cases. The following coats will harden overnight or even sooner.
AkDan
Posts: 172
Joined: Wed Oct 27, 2004 2:19 pm

Post by AkDan »

Glenn,

Thanks! I was talking to my dad tonight and ran the SE by h im, he also mentioned to ground it. Helluva idea. Never would have thought a wood boat would conduct electricity.....but it sure as heck did!!!


I do have some questions then about humidity.

You see today it was -48F (high only hit -32) Right now it shows the humidity as NA, but when it does register it's usually quite high, even though it's drier then a popcorn fart.

The other half is the garage is heated by a hot water heater that blows some serious air. I was going to run a spacer of light plastic drop cloth to keep the breeze away from my spray booth that is also the light drop cloth completely around the canoe and also on the ceiling. The first time I hung this to epoxy the canoe originally, the dust immediatly was stuck on the plastic.

So, can you get TO MUCH humidity for varnishing?
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Glen Smith
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Location: Baie-St-Paul, Quebec, Canada

Post by Glen Smith »

I have a controlled shop so I have never had any humidity problems but in the case of the Epifanes High Gloss I use they recommend a maximum of 85% for the one component varnish and 70% for the two component product.

If the humidity is too high it can slow down the cure speed and with some products it can make the varnish turn milky. Perhaps the manufacturer of the product you are going to use has some info on their website, or even on the varnish can.
AkDan
Posts: 172
Joined: Wed Oct 27, 2004 2:19 pm

Post by AkDan »

Thanks again! Yup read the can, was going to call them tomorrow (my saturday), and talk to them more about it.

I was thinking of getting a boiling tea kettle going as I dont really have anything portable that will boil more then that. Let it run for a few hours and try things out. I figured maybe by stretching a piece of the drop cloth as another barrier on the opposite side of the spray booth (which would make one on each outside and one that completely encirlces the canoe), it would allow that little pot to be more effective in the area I'm working?

Or would it be better to use the big propane style turkey deep fryers? My father inlaw does have one, somewhere though we are not sure where I'm sure I know someone else who I can borrow one from. Was worried that it might put out to much moisture. The garage is a large 2 car garage, again heated by a hot water heater that blows a lot of air so there is way to much circulation in that shop at any one time to be varnishing without some kind of barrier to keep it from blowing dust all over hill and dale.
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Glen Smith
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Location: Baie-St-Paul, Quebec, Canada

Post by Glen Smith »

Ideally, you should have a hygrometer in there so you know exactly how humid it is. Even a cheap one will work fine for this purpose. During the Winter my shop is only at about 35% humidity but that is perfect for the Epifanes. When I tried a water-borne finish, they specified a humidity around 50% so I mopped the floor and that worked fine for me. If you have the canoe enclosed in a booth, it shouldn't be too hard to raise the humidity to a workable level.
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Juneaudave
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Post by Juneaudave »

Dan...one of the best "easy" tips I ever got was to simply snitch your wife's spray bottle of water and spray the floor before varnishing. I can't tell whether it simply keeps dust from raising up, reduces the electrostatic whachamacallit, or raises the humidity. Anyway, it sure seems like it lessens the amount of dust for me!!!! Keep warm....I can't remember when it was as cold up there as it has been this week!!!!
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